/****************************************************************************
 *
 *   Copyright (c) 2019 PX4 Development Team. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name PX4 nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

#pragma once

#include "work_item.hpp"
#include <px4_platform_common/hrt_call.h>

namespace px4
{

/**
 * @class ScheduledWorkItem
 * @brief Work item that can be scheduled with timing constraints
 *
 * ScheduledWorkItem extends WorkItem to support time-based scheduling:
 * - ScheduleDelayed(): Run after a delay
 * - ScheduleOnInterval(): Run periodically
 * - ScheduleAt(): Run at a specific time
 *
 * Uses hrt_call for high-resolution timing.
 */
class ScheduledWorkItem : public WorkItem
{
public:
	/**
	 * @brief Check if the work item is currently scheduled
	 * @return true if scheduled (timer active), false otherwise
	 */
	bool Scheduled() { return !hrt_called(&_call); }

	/**
	 * @brief Schedule next run with a delay in microseconds
	 * @param delay_us The delay in microseconds
	 */
	void ScheduleDelayed(uint32_t delay_us);

	/**
	 * @brief Schedule repeating run with optional delay
	 * @param interval_us The interval in microseconds
	 * @param delay_us The initial delay (optional) in microseconds
	 */
	void ScheduleOnInterval(uint32_t interval_us, uint32_t delay_us = 0);

	/**
	 * @brief Schedule next run at a specific time
	 * @param time_us The absolute time in microseconds
	 */
	void ScheduleAt(hrt_abstime time_us);

	/**
	 * @brief Clear any scheduled work
	 *
	 * Cancels the hrt_call timer and removes the item from the work queue.
	 */
	void ScheduleClear();

	/**
	 * @brief Print run status with period information
	 */
	virtual void print_run_status() override;

protected:
	/**
	 * @brief Constructor
	 * @param name Work item name
	 * @param config Work queue configuration
	 */
	ScheduledWorkItem(const char *name, const wq_config_t &config) : WorkItem(name, config) {}

	/**
	 * @brief Destructor
	 */
	virtual ~ScheduledWorkItem() override;

private:
	/**
	 * @brief Pure virtual run method (must be implemented by derived classes)
	 */
	virtual void Run() override = 0;

	/**
	 * @brief Trampoline function for hrt_call callback
	 *
	 * This static function is called by the hrt_call timer.
	 * It calls ScheduleNow() to add the work item to the work queue.
	 *
	 * @param arg Pointer to the ScheduledWorkItem instance
	 */
	static void schedule_trampoline(void *arg);

	hrt_call_t _call{};  ///< High-resolution timer callback structure
};

} // namespace px4

